Chain with coded links

ABSTRACT

The present invention discloses a chain where, upon the stressing of the chain, the links automatically arrange themselves with respect to one another in terms of their position in the chain, preventing any undesired link. A link can be developed in the form, in top view, of a drop or in the form of a keyhole. The described chain is not only suitable for application in lashing loads, but also for use with the manipulation of all accessory chain parts, in which the placement of a link is required, for example shortening hooks, shortening straps or the like.

[0001] The invention relates to a link chain with coded chain links for the oriented emplacement of such a chain link into a chain link reception, wherein the coding of the chain links is formed thereby that the maximum outer width of the chain links in the region of their halves pointing in the direction of the load is smaller than in the region of the other halves.

[0002] Link chains with chain links coded in this manner are applied for example for lashing loads. For this purpose the free end of the link chain is fastened on the load to be lashed tightly and a chain link is inserted into a tightening device for tightening the chain. The chain is subsequently tightened with the tightening device. In order for the link chain to be loadable according to specification, it is essential that the chain link placed into the chain link reception of the tightening device engages the chain link reception with its half pointing toward the load. If the load is secured to the other half of this chain link, the link chain is not loadable with its nominal load. For this reason link chains have been developed whose chain links have a placement coding, such that the oriented emplacement of such a chain link in the chain link reception is possible in the specified direction pointing toward the load. This known coding is formed by material of the longitudinal shanks, which is reshaped in the course of a stamping for the development of cams projecting outwardly from the two longitudinal shanks. The inner width of a chain link coded in such manner is not affected by this stamping for the development of said coding. Through these cams the maximum width of such a coded chain link in the region of its half not pointing toward the load is greater than the outer width of the chain link in the region of its segment to be inserted into a chain link reception matched to this width. Such a chain link can consequently only be inserted with its narrower half into such chain link reception. In this manner incorrect insertion is effectively prevented.

[0003] Such chain links have been produced for many years and have been applied in unchanged form. Even if with these link chains incorrect handling of such a link chain is effectively counteracted when placing a chain link into a chain link reception for lashing loads, nevertheless, disadvantages are tolerated. These disadvantages relate to the handling of the known link chains, since the chain links become jammed with one another. Before in the case of such a link chain load is placed onto the chain, it must therefore be ensured that the individual chain links are not jammed with one another. The handling of such a link chain thereby entails effort and expenditures.

[0004] Building on this discussed prior art, the invention therefore addresses the problem of further developing an above described link chain according to the species such that jamming—as described above—is prevented.

[0005] This problem is solved according to the invention thereby that the inner width of the chain links corresponds at least to the length of the longest axis cutting across the material forming the cross sectional area of the subsequent chain link joined with this chain link.

[0006] In this link chain jamming is effectively prevented thereby that it is ensured that, independently of the position of the individual chain links with respect to one another, these links, upon the stressing of the link chain according to specification, arrange themselves with respect to one another in terms of their position without such chain link arrangement according to specification being prevented through the coding. The cross sectional shape of the material forming the chain link is usefully uniform over its entire extent. Preferred is a round, in particular circular, cross sectional shape.

[0007] The inner width of the coded chain links is usefully less than the twofold diameter of the material, for example wire, employed for the development of the chain link.

[0008] Apart from a uniform cross sectional shape, chain links are preferably employed, which have the identical material thickness over the extent of the chain link. In such an implementation, a chain link can be developed in the form, in top view, of a drop. However, in order to have available longitudinal shanks extending in segments parallel to one another in that half of the chain link pointing toward the load with which this chain link can be placed into a chain link reception, one embodiment provides developing the coded chain links, in top view, in the form of a keyhole.

[0009] The described link chain is not only suitable for application in lashing loads, but fundamentally in connection with the manipulation of all accessory chain parts, in which the emplacement of a chain link is required, for example shortening hooks, shortening straps or the like.

[0010] In the following the invention will be described in conjunction with an embodiment example with reference to the enclosed Figures. Therein depict:

[0011]FIG. 1 a top view onto a chain link coded with respect to its direction of insertion into a chain link reception according to a first embodiment,

[0012]FIG. 2 a top view onto a chain link coded with respect to its direction of insertion into a chain link reception according to a further embodiment,

[0013]FIG. 3 a representation of a link chain section formed of chain links corresponding to those of FIG. 1 shown adjacent to a shortening claw with a chain link reception, and

[0014]FIG. 4 the shortening claw of FIG. 3 with a chain link placed into the chain link reception.

[0015] A chain link 1 of a link chain is coded with respect to orientation for insertion of the chain link 1 into a chain link reception, for example a shortening claw. This placement coding is formed in the chain link 1 thereby that the half 2, in the FIG. 1 the lower one and pointing toward the load or toward the load hook, has a lesser outer width b_(a1) than the maximum outer width b_(a2) in the region of the upper half 3. The inner width b_(i) of chain link 1 is more narrow in the lower half 2 than in the upper half 3. The inner width b_(i) is in every case at least as large as the longest axis cutting across the cross sectional area of chain link 1 or of the material forming the chain link 1. In the embodiment example depicted in FIG. 1 the chain link 1 has a circular cross sectional shape as is represented in FIG. 1 by the two cross sections. Depicted is in each case a cross sectional area of the chain link 1 or of the material forming the chain link, which, in the depicted embodiment example, is a wire, in the region of the lower and in the region of the upper half 2 or 3, respectively. The cross sectional area is also dimensioned of uniform size over the entire chain link 1. Consequently, the longest axis cutting across the cross sectional area of chain link 1 is any axis which is tangential to the center point of the cross sectional area or crosses it. However, the inner width b_(i) is usefully no greater than the twofold diameter of the wire employed for developing the chain link 1.

[0016] In the lower half 2 of the chain link 1 the longitudinal shanks, at least in segments, are provided such that they extend parallel to one another. This segment of chain link 1 serves for the insertion into a chain [link] reception.

[0017] A link chain comprised of chain links 1, does not entail the hazard that individual chain links 1 become jammed with one another. Rather, the dimensioning of the inner width b_(i) ensures that each subsequent chain link 1 joined in the chain link 1 can align itself as specified when the link chain is raised or when a load is secured to it.

[0018]FIG. 2 depicts in top view a further chain link 4 coded with respect to its placement orientation for the formation of a link chain. The chain link 4 has the same properties as chain link 1 of FIG. 1. In contrast to the formation of chain link 1, in the chain link 4, starting with the upper maximum outer width b_(am) serving for coding, the two longitudinal shanks 5, 6 are inclined toward one another, such that the outer width b_(a) in the region of the lower half is smaller than the outer width b_(am).

[0019]FIG. 3 depicts a section of a link chain 7, which is made up of several chain links 1. The link chain 7 or a chain link 1 of the link chain 7 is intended to be placed into a shortening claw 8. For this purpose the shortening claw comprises in the lower region a chain link reception 9 developed in the manner of a pocket. The inner clearance b of chain link reception 9 corresponds substantially to the outer width b_(a1) of chain link 1 in the region of its lower half 2. Between the two dimensionings b and b_(a1) only enough tolerance is provided for the chain link 1 with its lower half 2 to be readily placed into the chain link reception 9 of the shortening claw 8.

[0020] The chain link 1 emplaced in the chain link reception 9 is depicted in FIG. 4. This representation shows clearly that the placement of the chain link 1 with its half 3, shown in the Figures as the upper one, would not be possible due to the greater outer width b_(a2). After all, the inner clearance b of the chain link reception 9 is smaller than the outer width b_(a2) of chain link 1. For this reason, a chain link 1 can only be placed in its specified orientation into the chain link reception 9 of the shortening claw 8. Since the lower half 2 of each chain link 1 is in each instance pointed toward the load or toward a load hook, in the case of link chain 7 there is never the hazard that a chain link 1 could be placed with incorrect orientation into the chain link reception 9 of the shortening claw 8.

[0021] List of Reference Symbol 1 Chain link 2 Half pointing toward the load 3 Half pointing away from the load 4 Chain link 5 Longitudinal shank 6 Longitudinal shank 7 Link chain 8 Shortening claw 9 Chain link reception b Inner clearance b_(a) Outer width b_(a1) Outer width b_(a2) Outer width b_(i) Inner width 

1. Link chain with coded chain links (1, 4) for the oriented placement of such chain link (1, 4) into a chain link reception (9), wherein the coding of the chain links (1, 4) is formed thereby that the maximum outer width (b_(a1), b_(a)) of the chain links (1, 4) in the region of its half (2) pointing in the load direction is smaller than in the region of the other half (3), characterized in that the inner width (b_(i)) of the chain links (1, 4) corresponds at least to the length of the longest axis cutting across the cross section area of the material forming a subsequent chain link (1) joined (5) to this chain link (1).
 2. Link chain as claimed in claim 1, characterized in that the material forming the chain link (1, 4) has the same cross sectional shape over the entire extent.
 3. Link chain as claimed in claim 2, characterized in that the chain links (4) are formed in the shape of a drop.
 4. Link chain as claimed in claim 2, characterized in that the chain links (1) are formed in the shape of a keyhole, wherein in the region of the half (2) pointing toward the load of chain link (1) the two longitudinal shanks are disposed such that they extent parallel to one another.
 5. Link chain as claimed in one of claims 1 to 4, characterized in that the cross sectional shape of the chain links (1, 4) is circular.
 6. Link chain as claimed in one of claims 1 to 6, characterized in that all chain links (1) of the link chain (7) are coded. 